[171] On Friday
evening, 4 October 1957, man's long dream of spaceflight became
reality with the launching of Sputnik I. Most Americans were
surprised, not only by the feat itself but that the Soviets had done
it first.

There was no lack of public forewarning about
the coming age of spaceflight, however. In July 1955, the United
States had announced its intention to launch satellites as part of
the scientific activities of the International Geophysical Year which
was to begin in mid-1957, and this was immediately followed by press
articles that the Soviets were making similar plans. In the United
States, the satellite activity became Project Vanguard, authorized in
September 1955.

Vanguard was the culmination of a decade of
scientific research of the upper atmosphere using balloons and
sounding rockets, of increasing pressure by groups who saw the
feasibility of spaceflight and made realistic proposals, and finally,
of the interest and backing of the scientific community through the
National Academy of Sciences. The last was essential, for many
earlier and sound space proposals had been treated with disdain. Some
of this attitude may have come from longtime exposure to grand and
impractical schemes and science fiction. Even the ideas of such
scientists and engineers as Tsiolkovskiy, Goddard, Oberth, and von
Braun had failed to arouse much more than transient public interest.
The wartime scare caused by the German rockets had long since
receded, and by the late 1940s even the the military services were
hard pressed to justify space projects-in spite of the obvious
advantages of reconnaissance, communications, and meteorological
satellites. International interest in cooperating to study the upper
atmosphere and space phenomena using high-altitude probes and
satellites became a major driving force, but it evolved so gradually
during the early 1950s that the public scarcely took notice. After
the 1955 announcement, Project Vanguard proceeded slowly and with
little publicity.

Parallel with scientific interest in space was
military interest. During the heyday of ballistic missile development
during the 1950s, effort was concentrated on long-range missile
capability, but engineers were well aware that the same missiles,
more powerful than Vanguard, could be modified to provide the
additional velocity needed to launch satellites.

The Soviet Sputnik I provided the spur for
action in this country. The news media reflected astonishment,
dismay, and fear. American pride was hurt, competitive spirit
[172] aroused, and a determination to "catch up" with
and exceed the Russians became evident.

In previous parts, we have examined the growth
of liquid hydrogen technology and its potential application for
rockets and aircraft. In this final part, we will examine the events
leading to the decision to use liquid hydrogen in two launch vehicles
for the great space accomplishments of the 1960s and 1970s. To do so,
we need to understand something of the antecedents of these
vehicles-the ballistic missiles of the 1950s. Also pertinent is the
competition among several government organizations for a role in
space and the formation of the National Aeronautics and Space
Administration. Throughout this discussion, emphasis will be on
launch vehicles and the considerations that led to the use of liquid
hydrogen.